Even systemically administered antibacterials and antimycotics may be classified in other groups if their target is exclusively local, e.g. the skin - D01 - Antifungals for dermatological use

Inhaled antiinfectives are classified in J.

The DDDs for the antiinfectives are as a main rule based on the use in infections of moderate severity. However, some antiinfectives are only used in severe infections and their DDDs are assigned accordingly. The DDDs assigned are based on daily treatment. The duration of the treatment periods is not taken into consideration. For antiinfectives given in a high initially starting dose followed by a lower daily "maintenance" dose, the DDDs are based on the "maintenance" dose if the total duration of the treat-ment course is more than one week. If, however, the treatment course is 7 days or less, the DDDs are assigned according to the average daily dose i.e. the total course dose divided by the number of treatment days (e.g azithromycin).

This group comprises antibacterials for systemic use, except antimycobacterials, which are classified in J04. The antibacterials are classified according to their mode of action and chemistry.

Combinations of two or more systemic antibacterials from different third levels are classified in J01R, except combinations of sulfonamides and trimethoprim, which are classified at a separate 4th level, J01EE.

Combinations of antibacterials with other drugs, including local anesthetics or vitamins, are classified at separate 5th levels in the respective antibacterial group by using the 50-series. Common cold preparations containing minimal amounts of antibacterials are classified in R05X.

Inhaled antiinfectives are classified here based on the fact that preparations for inhalation can not be separated from preparations for injection.

This group comprises imidazole antibacterials acting through active metabolites in anaerobic bacteria. Only formulations for parenteral use of e.g. metronidazole are classified in this group. Oral formulations and suppositories of imidazole derivatives are classified in P01 - Antiprotozoals. Pessaries are classified in G01 - Gynecological antiinfectives and antiseptics.

The DDDs for the parenteral imidazole formulations are based on the treatment of anaerobic bacteria infections.